Asgard Aviation System Definition Review

1. Logan Waddell Morgan Buchanan Erik Susemichel Aaron Foster Asgard AviationSystem Definition Review Craig Wikert Adam Ata Li Tan Matt Haas

2. Outline • Mission Statement • Major Design Requirements • Concept Selection • Overview • Pugh’s method • Advanced Technologies • Technologies incorporated • Impact on sizing • Propulsion Selection • Constraint Analysis • Major performance constraints • Basic assumptions • Constraint diagrams • Sizing Studies • Design Mission • Current Sizing Approach • Initial center of gravity, stability and control estimates • Summary

3. Mission Statement To design an environmentally responsible aircraft that sufficiently completes the “N+2” requirements for the NASA green aviation challenge.

4. Major Design Requirements • Noise (dB) • 42 dB decrease in noise • NOx Emissions • 75% reduction in emissions below CAEP 6 • Aircraft Fuel Burn • 40% Reduction in Fuel Burn • Airport Field Length • 50% shorter distance to takeoff * *ERA. (n.d.). Retrieved 2011, from NASA: http://www.aeronautics.nasa.gov/isrp/era/index.htm

5. Design Mission

6. Aircraft Concept Selection • Eight Initial Concepts • Pugh’s Method • Two Result Concepts

7. Aircraft Concepts 1 2 3 4 5 6 7 8

8. Pugh’s Method Process • Eight designs were generated and sketched. • A baseline concept was chosen to be the reference or datum. • Each design was evaluated for each criterion • Each design was assigned a ‘+’,’-’, or ‘s’ based from the datum. • All criteria was equally weighted. • The ‘+’,’-’, and ‘s’ were totaled • The two concepts with the most ‘+’ were discussed and chosen • A second Pugh’s method was run with a different concept being the datum. • The results were collected as with the first run. • Two concepts were selected for further investigation.

9. Pugh’s Method (1st run) DATUM DATUM

10. Pugh’s Method (2nd run)

11. Concept Selection • Both concepts had best results from Pugh’s Method 1 • Tube and Wing design with advanced technologies • Tube and Wing design • “H-tail” with two engines mounted in-between • Swept back wings • Noise shielding • Technologies • Winglets • Laminar Flow • Efficient Engine • Composite 2

12. Two Class System • Seating • 4 rows 1st Class • 34 rows Economy Class • 250 passengers • Seat Pitch • 39 inches 1st Class • 34 inches Economy Class • Seat Width • 23 inches 1st Class • 19 inches Economy Class

13. One Class System • Seating • No First Class (Low Cost Carriers) • 44 rows Economy Class • 303 passengers

14. Economy Class Section View • Fuselage Height = 16.5 feet • Aisle Height = 6.5 feet • Head Room = 5.5 feet

15. 1st Class Section View • Seat Width = 23 inches • Cargo Area = 5 feet

16. Advanced Technology Spiroid Winglets • Pros: • 6-10% reduction in fuel consumption (GII) • Improved climb gradient • Reduced climb thrust • 3% derate (737-300), resulting in reduction of the noise footprint by 6.5% and NOx emissions by 5% (blended) • Reduced cruise thrust • Improved cruise performance • Direct climb • Good looks • Cons: • Additional weight > 1000lbs • Could distort under loads causing performance loss or aerodynamic problems • Complexity to manufacture • Unknown effects during icing conditions Aviation Week & Space Technology, August 2, 2010. "Head Turning Tip" by William Garvey, "Inside Business Aviation" column, p60. http://www.b737.org.uk/winglets.htm http://www.aviationpartners.com/future.html

17. Composite Materials • 100 % Composite Aircraft • Lighter weight and stronger than Aluminum • Modeled as 20% reduction in empty weight • Additional Benefits of Composite Materials • Corrosion and fatigue benefits • Reduce the amount of fasteners needed • Composites used in acoustic damping • Thermal transfer system • Extended laminar flow • Disadvantages • High costs • Difficult crack detection *Boeing *http://www.designnews.com/article/14313-Boeing_787_Dreamliner_Represents_Composites_Revolution.php

18. Advanced Technology Landing Gear Fairings • Reduces the noise in the mid and high frequency domain compared to the plain landing gear configuration up to 4.5 dB* • Reduces vortex shedding due to bluff-body nature of nose and main landing gear** • Modeled as increase in empty weight *Molin, N. (2010). Perforated Fairings for Landing Gear Noise Control. Retrieved from eprints.soton.ac.uk: http://eprints.soton.ac.uk/43011/1/paper_vancouver_noabsolute_small.pdf • **Bruner, D. S. (2010). N + 3 Phase I Final Review. NASA ERA (p. 94). Northrop Grumman.

19. Hybrid Laminar Flow Control • Active drag reduction technique • Applied to wing, tail surfaces, and nacelles can achieve a 15% drag reduction* • Reduces fuel by ~ 5%** • Increases cost of maintenance by ~ 2.8%** • Increases DOC by ~0.8%** • Increase in empty weight *Archambaud, D. A. (2007). Laminar-Turbulent Transition Control. 2. ** Joslin, R. D. (1998). Overview of Laminar Flow Control. NASA (p. 18). Langley Research Center. *Clean Sky

20. Engine Selection • Engine type: Geared Turbofan • Gearbox allows fan to run at lower speeds than compressor and turbine, improving efficiency. • Provides 12%-15% improvement in fuel burn range, 50% NOx emissions reduction, and 20 dB decrease from level 4 noise standards Courtesy of Tosaka Courtesy of Airliners.net

21. Engine Sizing Approach • Using NASA Geared Turbofan data to approximate baseline performance of engine • Plan to use data to find fuel flow and SFC curve fit predictions as function of Mach #, altitude, and throttle setting • Will need to use adjustment factors to size engine to thrust requirements of aircraft • Also adjustment factors for implemented technologies will also need to be incorporated

22. Engine Sizing cont. • Compared aircraft concepts to Bombardier C-series airplane that will be powered by Pratt & Whitney GTF engines

23. Technologies for Improvement • Orbiting Combustion Nozzle (R-Jet Engineering) • Combustor employs rotating blades inside inner casing • Uses 25% less fuel and cuts CO2 and NOx emissions by 75% • Reduces size and weight of engine while producing same thrust

24. Technologies cont. • Noise Reduction Technologies • Swept/Leaned Stators • Scarf Inlet • Chevron Nozzle Images Courtesy of NASA Research

25. Technologies cont. • Liquid Hydrogen Fuel • Provides more energy and reduces fuel weight • Combustion of LH2 : • H2 + O2 + N2 = H2O + N2 + NOx • No CO2 emissions/lower NOx emissions • Drawbacks: • Fuel must be stored in cryogenic tank • Added tank structure could cause fuselage to be less aerodynamic

26. Constraint Analysis & Diagrams • Performance Constraints • Basic Assumptions • Constraint Diagrams

27. Major Performance Constraint Analysis • top of climb (1g steady, level flight, M = 0.8 @ h=35K, service ceiling) • landing braking ground roll @ h = 5K, +15° hot day • second segment climb gradient above h = 5K, +15° hot day

28. Updates Since SRR • Conventional with New Technologies

29. Basic Assumption for Concept 1Conventional with New Technologies

30. Constraint Diagrams for Concept 1 TSL/W0 =0.32 W0/S =106 [lb/ft2]

31. Updates Since SRR • Conventional H-tail with Engines Mounted in Between

32. Basic Assumption for Concept 2Conventional H-tail with Engines Mounted in Between

33. Constraint Diagrams for Concept 2 TSL/W0 =0.35 W0/S =98 [lb/ft2]

34. Trade Studies of Performance Requirements • Trade Studies are ongoing • Current Trade-offs • Conventional with New Technologies Geared Turbofan: Less Fuel Weight vs. More Drags Hybrid Laminar Flow Control: 12-14% Less Drags vs. 2.8% More Cost Landing Fairing: Reduce noise vs. More Weight • Conventional H-tail with Engines Mounted in Between Improved Control at Low Airspeed and Taxiing vs. More Drags Smaller Vertical Stabilizer vs. Heavier Horizontal Tail

35. Sizing Code Incorporation • Using NASA Geared Turbofan data to approximate baseline performance of engine • Plan to use data to find fuel flow and SFC curve fit predictions as function of Mach #, altitude, and throttle setting • Will need to use adjustment factors to size engine to thrust requirements of aircraft • Also adjustment factors for implemented technologies will also need to be incorporated

36. Sizing Code • Using MATLAB software, first order method from Raymer • Used several inputs to determine the size of pre-existing aircraft for validation

37. Status of Sizing Code • Currently the code calculates coefficients of lift and drag needed for fuel burn predictions • Future work needed includes the component weight build up

38. Incorporating Drag • Drag values affect the sizing and are necessary in order to predict the takeoff weight Included in the equation are the parasitic, induced, and wave drag

39. Validation • Boeing 767-200ER • Passenger Capacity: 224 • Range: 6,545 nmi • Crew: 2 • Cruise Mach: 0.8 • Max Fuel Capacity: 16,700 gal

40. Validation continued • The sizing code predictions are accurate • The error factor for the takeoff weight is:

41. Selected Concept Predictions Tube and wing with new technology L/Dcruise = 17.2, AR = 7.8 Tube and wing with H-Tail L/Dcruise = 16.9, AR = 7.8

42. Center of Gravity, Stability, and Control Estimates Center of Gravity Neutral Point

43. Tail Sizing • Current Approach • Using Raymer Equations (6.28) and (6.29)

44. Concept 1 Concept 2 767-300 • Length: 180’ 180’ 3’’ • Wing Span: 157’ 156’ 1’’ • Height: 51’ 51’ • Fuselage Height: 17’ 17’ 9’’ • Fuselage Width: 16’ 16’ 6’’

45. Concept 2 Concept 1 767-300 • Length: 180’ 180’ 3’’ • Wing Span: 165’ 156’ 1’’ • Height: 45’ 51’ • Fuselage Height: 17’ 17’ 9’’ • Fuselage Width: 16’ 16’ 6’’

46. Design Requirements Compliance Matrix

47. Next Steps • Finalize Sizing Code • Complete Component Weights • Determine Aircraft details • Noise • Cost • Stability and Control